Rough Running all of a sudden

[ASM]

Took the S3 out yesterday morning early I admit and it started without a problem but was running fairly roughly which it normally does until warm. These symptoms however did not stop and eventally she started to cut out when stationery.

I managed to get to work and of course when I went to leave last night she coughed and splutted and would not start.

She turns over ok but will not start and judging by the fumes could be running rich as well? I'm running her on Optimax for the first time and wondered if that could have started something?

Looking at the bible there seems to be a number of causes but I intend to unplug the ECU, engage default settings and hopefully that may at least get the car home?

Does this sounds familiar to anyone else as I'm sure it's not a serious problem?

Any suggestions would be very helful.

Cheers

[shnozz]

have you tried unplugging the throttle pot to see if its any better? Doesnt sound exactly like the usual TP symptoms but always worth a check.

[andyf007]

Check the ignition leads, etc. Make sure they are all plugged fully in, and fire her up in the dark and have a look.

[ASM]

I've taken out all the plugs and each one was flooded with fuel so after cleaning them up and checking the gaps put them back. She started by was still running very roughly.

I then checked the air filter which once removed improved the situation so I have now cleaned it and will put back on car pending delivery of new item. The existing filter on the car is the Pipercross variety, is there a better option here such as a K&N fittment?

After all of this and unplugging the ECU I managed to get home but she is what feels like running on 4 or 5 cylinders? I reckon I could either have dodgy leads or a sensor has gone down as I checked the distributor for dampness but it was fine?

Any other suggestions to narrow down?

[andyf007]

If all the plugs were wet, look to the coil ht lead, cap & rotor arm. Check for arcing around the coil end of the ht lead to the 2 spade terminals. Check for a broken wire at these terminals too. Check the same around the cap (difficult to see arcing in there when it's not dark). Check inside the cap too, especially the small graphite bush in the centre that contacts the rotor arm. These have a habit of become erratic when well worn. I would recommend replacing these parts anyway as a precaution.

If it's a non-cat version, check the airflow meter plug connectors too, make sure they are seated properly.

Keep us posted.

Andy

[ASM]

Andy,
Thanks very much, I will check this out asap this week and replace as you recommend, fingers crossed this solves the issue.
I'll let you guys know.
Cheers
Rob